North Star BHP Steel When North Star BHP Steel installed a new electric steel mini-mill in Delta, Ohio, management had concerns about power quality and wanted to monitor plant power usage closely. It was the first electric arc furnace load on the Toledo Edison grid. The company contracted with Power Systems Development, Inc. (PSD) of Canton, Ohio to design and build the substation for the new mini-mill. PSD turned to Programmable Control Services, Inc. (PCS) to provide the substation SCADA and power monitoring system. An Allen-Bradley PLC-5/60 was used as the master system controller. A PC running windows based software provides operator interface and connects to the plant wide Ethernet system. Seventy Allen-Bradley 1400-PD power monitors throughout the plant provide load data and circuit breaker status for switch gear, plant unit substations and local MCCs. The power monitors also act as remote I/O to allow remote shedding and restoration of selected loads. Communications and security was a key issue with the system. Fiber-optic cabling was used extensively for both Remote I/O and Data Highway Plus. Its use prevents the high noise levels inherent in substations and electric arc furnace installations from degrading system functionality and allows longer distances to be covered. The system allows operators anywhere in the plant to see the status of the electric power system. The interface with Toledo Edison allows for load shedding as needed. Better coordination between the substation control and mill activities is achieved with the Data Highway Plus channel connected by fiber optics to the mill control PC, the OIT, the mill PLCs and the programming terminals. Mill operators are able to control the static VAR controller remotely through the SCADA system.